For many database configurations, it is desirable to have a physical replica or a physical standby that replicates the data from one or more primary or production databases. By maintaining a standby database as a replicated copy of a primary database, the physical standby can provide data protection and redundancy through features such as database recovery, database failover, and test databases. Moreover, since many database workloads are biased towards a higher ratio of read queries compared to writes, the physical standby can also offload database read queries from the primary database, reducing processing burdens on production servers.
To address big data processing demands in the modern enterprise, many databases have migrated to multi-instance or multi-node database configurations. As a result, a significant volume of change records or redo records is generated for the primary database. The speed by which these redo records are applied on the standby database has a direct impact on key database performance metrics such as mean time to recovery and replication lag time.
On the other hand, the physical standby is often configured to apply redo as a single-node process, even when the physical standby is multi-node. The redo apply is thus unable to efficiently utilize all available hardware resources to keep pace with the large volume of redo records generated from the multi-node primary database. Accordingly, a single-node redo apply may become a serious performance bottleneck for the physical standby, negatively impacting database availability and query response times.
Based on the foregoing, there is a need for a method to provide an efficient and high performance redo apply for a physical standby.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.